Slate-frame



e. "B. THOMPSON,

Slate-Frame.

No. 227,662. "Patented 'May 18, 188Q.

N-FETERi PNOTO-UTMOGRAHLEB, WASHINGTON, D C.

ilNITED STATES PATENT OFFICE.

GEORGE B. THOMPSON, OF PITTSTON, PENNSYLVANIA.

SLATE-FRAM E.

SPECIFICATION forming part of Letters Patent No. 227,662, dated May 18,1880,

Application filed November 14,1879.

pecially in the class of slates termed noiseless, is generally much morethan the cost of the slate.

My invention contemplates the keeping by dealers of the various sizes ofslates framed in accordance with my invention, and also a supply of thedifferent sizes without frames, so that in case of breakage an unskilledperson may, without tools, put the frame of the broken slate uponanother slate of the same size, and thus save the cost of the frame.

The invention consists of a removable tubular elastic frame so formedand vulcanized as to be fitted and held upon the edge of the slateentirely or mainly by its own tension, and which derives a portion ofits cushioning or elasticity from the form in which it is vulcanized andfrom the air that is somewhat confined therein.

In the accompanying drawings, in which similar letters of referenceindicate like parts, A is the slate. B is the frame.

Figure 1 is a plan, showing the tubular frame B in place upon the edgeof the slate A. Fig. 2 is a section. Figs. 3 and 4 represent the mannerin which two or more slates may be connected by bands of rubber or othersuitable materials, 0 G, to make a folding or book slate.

The frame may be made by cutting from unvuloanized rubber tubing, ortubing made from other elastic gum or suitable materials, pieces shorterthan the perimeter of the slate, each of which may have its ends broughttogether and sealed, forming an endless tube. They should then be placedupon suitable forms corresponding with the shape of the slate, butsmaller, upon which they should be vulcanized or otherwise cured. Thisoperation is for the purpose of improving the fit of the frame at thecorners of the slate; but a fair fit will be obtained by vulcanizing theendless tube in the circular form that it will assume without the use ofthe forms. After vulcanizing the frame may be ripped open and sprungover the edge of the slate.

A good frame may be made by taking a piece of vulcanized rubber tubingand cementing, sewing, or connecting the ends by clips or otherwise, andslitting it to receive the edge of the slate.

The corners of the slate should be made circular, its entire edgesmooth, and the slate should be so ground or otherwise prepared as toleave it as thick or thicker at the edges than elsewhere, in order toprevent the edge and corners from cutting the frame.

The corners of the frame may be re-enforoed by increasing the thicknessof material, or by insertions of cloth, metal, or other suitable ma.-terial, which should be done before the frame is vulcanized.

To make the frames for the folding or book slates shown in Figs. 3 and4, two or more frames that have been made as previously described may beconnected together by cementin g thereto the strips or bands 0 O, whichshould be done before vulcanizin g, but may be done afterward.

There will be no necessity for fastening the frame to the slate, unlessit be to prevent its removal, as it will, by its own elasticity and theform in which it is vulcanized, firmly embrace the edge of the slate andmake a snug fit but if it is desired to secure the frame to the slate,it may be glued or cemented directly thereto, or to one or more piecesof rubber placed in holes made through the slate where the oppositeedges of the frame come in contact with the same 5 or it may be securedby stitches, clips, or otherwise; but in each case the fastening usedshould allow of the removal of the frame without injuring it, so that itmay be used upon other slates without being fastened.

I do not limit myself to the means herein described for manufacturing myimproved slate, as other means and devices will readily suggestthemselves.

I do not claim a rubber or elastic slate- 2. The combination of theslate A and the frame, broadly, as such frames are old but slittedtubular elastic frameB, forming an air- 10 What I do claim, and desireto secure by cushion, substantiallyas described and for the LettersPatent, ispurpose set forth.

5 1. As a new article of manufacture, an elas- GEORGE B. THOMPSON.

tic slate-frame consisting of an endless tube Witnesses: of vulcanizedrubber and slitted on its inner W. L. WATSON,

side, substantially as described. 0. S. CRANE.

